Composition and method of producing same



Feb. 18, 1941. G. JURKAT 2,232,389

COMPOSITION AND METHOD OF PRODUCING SAME Filed Aug. 7, 19159 sum 153mm:

' INVENTOR, HerkardJuzZmZ BY o flip ATTORNEY.-

Patented Feb. 18, 1941 UNITED STATES k COMPOSITION AND METHOD OF l PRODUCING SAME Gerhard Jurkat, Hoboken, N. I. Application August "I, 1939, Serial No. 288,869

15 Claims.

This invention relates to a new composition matter in general, and particularly to a new abrasive composition and the method of producing the same.

Abrasive compounds of different types are known; The present invention deals especially with a relatively soft, spongy abrasive compound, adapted for roughening and cleansing of various articles and materials, and for the application of cleansing, polishing, and coloring liquids.

Certain materials, such as' wool fabrics, cotton fabrics, camel hair fabrics, felt, suede, either artificial or natural, and other rough-surface leather or leather imitations of all descriptions,

the exposed or outer surface of which are intended to be of dull, instead of having a glossy finish, are rather difficult to keep in their original intended state, since they acquire after continuous use a greasy, objectionable gloss. Such gloss is due to the wearing oil of the tiny, short fibres purposely provided at the outer or wearing surface of the material. My invention is partioularly directed .to an abrasive composition which will facilitate cleansing and restoring the lost dull finish of such materials.

I have found that heretofore used devices intended for similar purposes are ineffective and insufllcient, and in most cases rather induce the undesirable gloss instead of removing same.

There have 'been used for similar purposes natu-' ral and artificial sponges and variously com- .pounded rubber compositions containing abrasives of one sort or another, which devices either fail in their intended purpose, or are unsuitable because of their extremely unreliable abrasive properties.

The present invention contemplates the production of an artificial sponge made of vulcanized rubber, wherein the non-porous walls surround- 40 ing .the pores of the sponge contain a combination of certain mineral and cellulose fibres or strands which are sointermixed with one another and so arranged in respect to the abrading surface of the composition that the ends of the fibres terminate at and always form a substantial portion of the abrading surface of the sponge.

I have found that 'by certain arrangements of the fibres or strands in certain proportions, these fibresor strands function somewhat similar to a combination brush and comb, wherein some of the bristles, such as the mineral strands, perform the function of roughening, while the vegetable or cellulose fibres or strands perform the function of combing the roughened surface to their origin-ally desired state.

In the production of my spongy abrasivecomposition, I have further discovered that by a judicious combination 'of cellulose and mineral fibres, I was able to reinforce the usually brittle mineral fibres, thus preventing them from 5 breaking and separating from the composition, and that I also reinforce the wall structure of the pores, and therefore strengthen the entire body of my composition.

I have further discovered that certain natural in vegetable fibres contain certain mineral salts, such as silicates and oxalates, which in themselves are mild abrasives, Such salts may be found, for instance, in sisal hemp, aloe fibres, straw, etc.

I have further discovered that it is essential that a major portion of the different types of fibres used must be so disposed that their ends assume a position at right angles to the abrading surface of my composition, or approximately20 thereto, and I prefer to so arrange either the mineral fibres alone or the mixture of mineral and vegetable fibres to maintain such position within my composition, whereby the useful life of the latter is considerably enhanced. In other 2 words, when the vegetable fibres are properly comixed with the mineral fibres and are arranged so that their ends always form an essential portion of the abrading surface of mycomposition, I actually reinforce the body of the sponge and 30 retard its wear to a marked extent. It is to be noted that all of the fibres, 'both mineral and vegetable, must be securely anchored in the nonporous walls of the sponge, so that they may not separate from the spongy body during operation; 35

Such disadvantage is very evident in heretofore produced abrasive compositions, where powdered or crushed glass, or glass in splinters, powdered carb orund'um, and milder abrasives of relatively short body length are employed. they 40 usually produce an excessive roughening for short time periods, and when the abrasives fall out from their holding mass, a lack of abrasive action follows.

mixed mineral and vegetable fibres, to which I preferably add a rubber composition to be partially vulcanized or pre-vulcanized, whereby the grouped fibres are held sufficiently together to permit their introduction into the mass, fromwhich my sponge rubber abrasive composition is made.

It is to be noted that due to the addition of mineral fibres or strands, the specific weight of my composition is considerably increased, and therefore requires a sufficient percentage of gasforming agents to produce the required pores in my sponge device. These pores are essential, especially for the purpose of absorbing cleansing, polishing or coloring material in liquid form, which is applied to the surface to be roughened during the roughening operation. Incidentally, such procedure more readily facilitates the introduction of such liquid matter, and apecially of coloring, due to the fact that the roughening operation so-to-speak opens the pores of the material to be treated, and permits the ready introduction of liquid matter into the open pores, -whereby a perfect result is obtained.

My composition may be produced in different ways, and I shall describe several of the major processes employed. In all of the processes I use as major ingredients natural rubber, such as Kongo or Peru rubber, to which I add artificial or substitute rubber, such as vulcanized oils known as factice. I preferably use white factice. Furthermore, I add a rather heavy percentage of a mineral filler, such as chalk or barium, also whatI term mineral wax, such as parafiin or ceresin, or both, a vulcanizing agent, such as sulphur, and various types of gas-forming agents, such as ammonium carbonate, oil of turpentine, a mixture of flour, alcohol or chloroform, or a mixture of ceresin and amylacitate. To the above composition I add a certain percentage of a mixture of mineral and vegetable or cellulose fibres in elongated form.

One of the processes employed consists of the following steps: 25 to 40 parts of natural rubber, such as Kongo rubber, is rolled to a plastic,

whereupon is added 8 to 12 parts of white factis;

25 to 40 parts of chalk and 8 to 12 parts of spun glass fibres and 5 to 9 parts of vegetable or cellulose fibres. The rolling is continued until all of the above ingredients are thoroughly mixed, whereupon I add 1.5 to 3 parts of ceresin, 1.5 to 3 parts of oil of turpentine, and 1.5 to 2.5 parts of sulphur. These added ingredients are now well intermixed with the previously rolled compound and the entire mass is repeatedly re-rolled and 'finally rolled to a desired thickness, placed into forms and vulcanized. The forms are preferably rectangular in shape and, depending upon their depth, smaller or larger pores are produced during vulcanization. When the forms are shallow, the pores are relatively small, whereas in a deeper mold, the pores grow correspondingly larger. Due to the fact that all abrasive fibres, both glass and cellulose, are elongated, and are introduced in a certain pre-arranged manner, the rolling operation preceding vulcanization causes the fibres to assume a so-to-speak one-directional position relative to the body of the mixture, whereby all non-porous walls of the cells or pores of A variation of the aforedescribed process is as follows: All the aforestated ingredients, with the exception of the glass fibre, are employed and are dealt with in the manner outlined, except that some of the vegetable or cellulose fibres are retained for later use, and only a relatively small percentage of cellulose fibres are mixed with the rubber composition. Before the mixture is ready to be vulcanized, the vegetable or cellulose fibres and the glass fibres are grouped into parallel relation with one another, and preferably are intermixed with a rubber compound, and subjected to a short period of pre-vulcanization.

The above indicated rubber composition is then rolled out into thin sheets which are cut to uniform sizes, whereupon I arrange several courses of superimposed layers, starting with a sheet of rubber composition, whereupon I place a layer of the mixed, pre-vulcanized cellulose and glass fibres, then another rubber composition sheet, another fibre layer, etc., until the top layer of a composition rubber sheet finishes the column. 'I'hereupon I compress all the super-imposed courses so that the rubber composition of the sheets absorbs the layers of the combination cellulose and glass fibres. After this compression the whole body is placed into forms and vulcanized. The finished product is then cut at substantially right angles to the longitudinal fibres, whereby pads are produced which may be provided with a suitable reinforcing backing for immediate use.

A slight modification of the immediately preceding method consists in the introduction of the combined cellulose and glass fibres in the form of twists, cords or braids, which are preferably vulcanized, and formed into layers, prior to the final vulcanization of the stocked-up courses of rubber composition and abrasive fibres.

While the above-described rubber composition produces a very good sponge rubber body, I have found that the following mixture may be employed with equally good success: I use 25 to 40 parts of Peru rubber, 15 to 25 parts of white factice, 1 to 2 parts of paraffin, 10 to parts of barium, 8 to 12 parts of chalk, and 6 to 9 parts of sulphur. The gas-forming agent in this composition consists of a mixture of 8 to 12 parts of flour, 6 to 8 parts of alcohol, and 2 to 12 parts of chloroform. Instead of this gas-forming agent, I may employ a composition consisting of 1 to 2 parts of ceresin with 8 to 12 parts of amylacetate. With either of the gas-forming agents I use 12 to 14 parts of glass fibres or strands mixed with 3 to 4 parts of vegetable or cellulose fibres. The procedure of forming alternate courses or layers of rubber composition and combination glass and vegetable fibres is the same as described above.

It is to be noted that inboth compositions stated herein the quantities or parts referred to indicate weights; that by cellulose fibres I understand fibres of vegetable origin, which however may be in spun form. Nevertheless, I prefer the use of natural vegetable fibres, such as mentioned before, since those fibres are capable of forming what may be termed miniature brushes which produce a combing action. This brush formation is due to the natural structure of the fibres which consists of a great number of very fine, hairy threads or filaments which spread out when subjected to friction, and more so when simultaneously exposed to moisture.

In order to graphically illustrate my method of producing an abrasive composition, from which handy abrasive pads may be made,I introduce the accompanying drawing, in which: i

Figure 1 is a finished pad ready for use without a backing.

of an abrasive pad with relatively large pores.

. Fig. 4 is a partial end view of alternate courses of rubber composition sheets and iayersof abrasive fibres employed inmy process prior to-the.

final vulcanization'step. p

Figs. 5 and 6 illustrate similar end views, wherein, however, the abrasive fibres are grouped or combined difi'erently.

of layers with parts ofthe diiferentlayers exposed. 4

Fig. 9 is a typical cross sectional viewtake on line 9-9 of Fig. 8. i

Fig. 10 illustrates a braided arrangement of vegetable and glass fibres.

Fig. 11 is a cross sectional view taken on line ll-li of Fig. 10.

Fig. 12 illustrates a cord-like grouping of table and glass fibres. I

Fig. 13 is acrosssectional view taken online i3-I3 of Fig. 12. l

Fig. 14 is an enlarged view of a portion of my finished abrasive material, prior to cutting it into pads, and I U f Fig. 15 is a microscopic enlargement of a portion of my abrasive pad produced by the aforedescribed method. I j Referring now specifically tothe drawing, pad ill of Fig. 1 is a typical illustration of a spongy vegeabrasive pad produced by my method and cut off frombody ll, shown in Fig. 14 of my finished composition. In Fig. 2 is indicated a portion of a pad l2, similar in all respects to pad I! of Fig. 1, which, however, is provided with a backing l3 to reinforce'the body of the pad. It will be observed that all the fibres which formthe abrasive elements of the pad are arranged vertically, as clearly indicated at M. In Fig. 12 it will be also seen that the pores of the spongy body are relatively small, whereas in Fig. 3 the pores are considerably larger. From this figure,-

"it will be evident that pad l5, provided with a backing l6, also carries in the substantially nonporous walls of its pores elongated abrasive fibres H, which are perpendicular to the abrading surface indicated at l8.

Referring to Fig.4, there are illustrated ,alternately super-imposed courses of rubber composition l9 and fibre layers 20. These fibre layersconslst of evenly intermixed loose mineral and cellulose fibres, arranged in parallel relation to one another and forming courses of uniform thickness. It will be observed that the bottom layer l9 and the top layer l9" aremade of rubber composition and that both these layers 1 are shown of the same thickness as rubber layers I9. I prefer, however, to employ thicker layers for the top and bottom.

Similar arrangements of alternate courses of table fibre strands, which are preferably prevulcanized and then uniformly placed between rubber layers 2|. This grouping of fibre strands is preferably accomplished by either forming fibre cords such as illustrated in Figs. 12 and 13,

or bya grouping of parallel loose strands of the type shown in Figs. 8 and 9.

Referring now to Fig. 6, there are again shown courses 2! of rubber composition, between which are arranged layers of grouped abrasive fibres, indicated at 24. These layers of abrasive fibres correspond to the braided form of fibres, observed in Figs. 10 and 11. In all types of fibre group- "ings it is preferable to pre-vulcanize the fibres together before forming them into even layers Fig. '1 is a plan view of a portion of a stack between the rubber sheets. 1

Obviously, all of the fibres, no matter in what form, are preferably arranged substantially parallel to one another or when grouped fibres are used, they are also arranged in longitudinal fashion and in one direction only, as clearly illustrated in Fig. '7. When the alternate courses of rubber sheets and fibre layers are stacked up to a desired height, they are forcibly compressed and placed into forms to be vulcanized. The finished product shown at H in Fig. 14 is then cut perpendicularly to the direction of the abrasive fibres.

Fig. 15 clearly demonstrated that the finished product is composed of a spongy rubber mass in which the substantially non-porous walls of the pores or cavities 25 are uniformly studded with,

the ends of the combined, evenly distributed abrasive fibres which form an essential part of the abrading surface of the finished product- While the aforedescribed processes, in conjunc tion with the accompanying drawing, and the ingredients mentioned represent the essential steps and arrangement to be followed in my method, and while I have stated certain proportions of the ingredients employed, and al-- though I am aware of abrasive compositionssusing similar ingredients, I believe to be the first who introduces into a spongy rubberbase a, mix ture or a combination of vegetable or cellulose fibres with mineral fibres, such as glass strands, whereby entirely new results are procured, in that the glass strands andthe fibre strands cooperate with one another so that while the former are utilizedfor toughening the material to be abraded, the latter comb the worked-out fibres, and while the abrasive action is taking place,

liquid matter, absorbedby the pores of the composition, may be conveniently and efficiently introduced into the newly abraded surface.

Furthermore, I believe to be the first who not only employs a combination of elongated mineral and cellulose fibres, but who, realizing the increased weight of the rubber tomposition due to the addition of heavy mineral fibres, incorpo rates new, efficient and sufficient gas-forming agents to provide, in spite of the increased weight of the body a sufficient amount, of pores in the finished product for effectively absorbing liquid agents to be introduced into the roughened surface of the material to "be treated.

I also believe to be the first, who has developed ter, and due to which wall-reinforcement of the cells the relatively infirm body of the whole structure is substantially strengthened, whereby at leasttwo types of elongated abrasive matby the useful life of the composition is materially increased.

Furthermore, I do believe to be the first to produce an abrasive implement in the form of a sponge, wherein the abrasive elements consist of a combination of at least two chemically and physically different types of elongated fibres, and wherein one type of fibres is of vegetable origin, while the other type is mineral, and wherein the vegetable fibres form effective reinforcements of the mineral fibres, and wherein the pores of the sponge serve not only for the purpose of absorbing liquids, from which the latter are discharged as needed, but wherein these are primarily desired for roughening, cleansing and coloring of relatively soft materials, they may be employed successfully for other purposes, such as scraping, cleaning or otherwise treating relatively hard surfaces, such as wood, metals, coats of paint, etc., provided that the abrasive matter used is suitably altered as to quantity and size.

It is quite obvious, therefore, that in order to meet various conditions and requirements dueto the fact that materials to be treated with my composition may differ in their physical characteristics, I wish it to be understood that I reserve for myself the right to make changes and improvements in both my process and the compositions stated, and in the proportions of and the ingredients used, without departing from the broad scope of my invention, as disclosed in the annexed claims.

I claim:

1. In an abrasive .composition, a substantially resilient base, such as a sponge rubber compound, a combination of elongated organic and inorganic abrasive fibres carried by the nonporous portions of the base so that at least the ends of the inorganic fibres terminate at the abrading surface of the base. a i 2. In an abrasive composition, a sponge ru ber base, a combination of glass strands and vegetable fibres carried by and imbedded in the base, and wherein the vegetable fibres reinforce the glass strands, and wherein the combined strands and fibres constitute reinforcements for the base body and are so disposed therein that their ends terminate at and always form an essential part of the abrading surfaceof the base, as the composition is being consumed.

3. As a new product, a resilient base containing a mixture of parallelly arranged elongated vegetable and mineral abrasive fibres.

4. As a new abrasive product, a spongy, resilient base containing and being reinforced by a mixture of substantially parallelly arranged, elongated cellulose and mineral abrasive fibres, the ends of which fibres always constitute an essential part of the abrading surface of the product. I

5. As a new abrasive product, set forth in claim 4, and wherein the base, proir to being cured, consistsof a composition of natural rubber, a rubber substitute, mineral filler, mineral wax, sulphur and a'gas-forming agent, and wherein the abrasive mineral fibres are spun glass.

6. As a new abrasive product, set forth in claim 4, and wherein the base, prior to being cured, consists of natural rubber, such as Peru rubber, rubber substitute, such as white factice; mineral filler, such as chalk; mineral wax, such as ceresin; a gas-forming agent, such as oil of turpentine; a vulcanizing agent, such as sulphur; and wherein the mineral fibres are spun glass strands, and wherein the cellulose fibres surround and reinforce said mineral fibres.

of rubber substitute, 1:; to 40 parts of mineral filler, ,l to 3 parts of mineral wax, 1.5 to 24 parts of a gas-forming agent and 1.5 to 9 parts of a vulcanizing agent, and wherein the mineral abrasive fibres form 8 to 14 parts, and the cellulose fibres 3 to 9 parts of the finished product.

8. A new abrasive composition comprising a resilient vulcanized rubber sponge 'body, wherein the walls of the pores contain and are reinforced by a mixture of elongated spun mineral and natural vegetable fibres so disposed that the ends of the fibres always constitute a substantial portion of the abrading surface of the composition.

9. The process of producing a new abrasive composition, which comprises rolling to a smooth, fiat body a quantity of natural rubber, adding thereto a rubber substitute, a mlneralfiller, elongated cellulose fibres, continuing the rolling operation until the ingredients are intermixed, thereupon adding mineral wax, sulphur and a gas forming agent, re-mixing by rolling all of the ingredients, rolling the mixture into thin sheets,

forming alternate courses of such sheets and of layer of evenly distributed, substantially parallelly arranged,-elongated mineral fibres, compressing the latter into the sheets, vulcanizing the compressed mass and cutting the vulcanized product at right angles to the direction of the mineral fibres.

10. The process of producing a new abrasive composition which comprises, firstly, rolling to a smooth, ,fiat body a quantity of natural rubber, secondly, adding thereto white factice, a mineral filler and elongated cellulosefibres, thirdly, 'con- I tinuing the rolling operation until all of the and surrounded by said cellulose strands, forming alternate courses of sheets of the mixed rubber mass and of layers of evenly distributed, parallelly arranged combined cellulose and mineral strands, compressing the combined strands into the sheets, vulcanizing the compressed. courses and forming abrasive pads from the vulcanized product by cutting the latter at an angle to the direction of the combined strands.

11. The process of producing a new abrasive composition as set forth in claim 10, and wherein said cellulose and mineral strands are grouped, combined and mixed together with a rubber composition and are partially vulcanized, before being formed into layers.

12. The process of producing a new abrasive composition as set forth in claim 9, and wherein said cellulose and mineral strandsiare mixed by twisting them into cords or braids, adding a sufficient amount of rubber to the twisted strand mixture and setting the strands by partial vulcanization prior to being formed into layers, and wherein said set cords or braids are arranged. closely together and substantially parallel to one another when formed into layers, and wherein the cords or braids of all layers are disposed in one direction only throughout the several courses between the rubber mass sheets before their compression and before the final vulcanization step.

13. The process of producing a new abrasive compound, which consists of preparing a rubber mass adapted to be converted by vulcanization into a sponge rubber base of relatively high speciflc weight, forming sheets from the mass, placing between each two superimposed sheets layers of the mixed fibres in uniform thickness so that the fibres are arranged in one direction only, compressing the sheets and fibre layers, vuicanizing the laminated structure and cutting pads from the vulcanized product at an angle to the direction of the fibres.

14. The process of producing a new abrasive implement, which comprises forming a vulcanizable sponge rubber base, introducing thereinto a mixture of elongated cellulose and mineral fibres so that upon vulcanization they will be uniformly distributed throughout the base and their major portion is disposed in one direction a backing to said pads.

- GERHARD JURKAT. 

